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CrossedUpChris
My experience with EDFs is limited to 2 unbranded plastic units that I've had off ebay in the UK.

1- 64mm 5 blade 3s edf unit. Not bad. I used it to power my second ever rc plane. It was a 70% ft viggen and it flew very nicely, but did require a lot of throttle. It lasted me all of the summer of 2014 flying about 4 or 5 times a week until the foam board finally gave up the ghost.

2- 64mm 12 blade 4s unit. Which i fitted to a 100% FT viggen. This unit was not so great and given it was only abiut £12 less than an alloy dps unit i regretted using it in a plane i put so much effort into. It totally hammered the batterries, emptying some high discharge 2200 nanotech batterries in 3 mins or less. The thrust was pretty pathetic too. I didnt measure it but i had to fly at WOT constantly.The tolerance between the fan and the housing looked huge. I did help it along with remote operated solid rocket booster though, link below.



From my experience I would only buy a reputable edf now and would be tempted to stick to 70mm or over.
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quorneng
Just to put the "other side of coin" cheap EDFs can in fact be quite effective but it all depends on the application.
Not unreasonably people look for the maximum thrust from a given fan diameter and accept the relatively short flight time. however if you look at the thrust/watt, particularly at part throttle, and the thrust/g then the cheap fans are not so bad.
The problem is you don't get that much thrust to start with so the planes weight and wing loading becomes key factors for success.
Using thin Depron sheet i have designed and built several EDFs, all scale, using cheap AEO EDFs ranging from 35 to 70 mm. What they all have in common is they are very light, have a low wing loading for an EDF and as a result only require relatively modest batteries.
This is probably the most bizarre so far.
Avatar1.jpg  Despite its looks it is not fast but then neither was the full size as it was intended purely for low speed research.
Only 28" span but nearly 6 ft long it weighs just 23 oz (652 g) ready to go and manages very nicely on an AEO 55 mm EDF. Hand launched and reasonably aerobatic it can cruise about for nearly 8 minutes on its 1800mAh 3s.
Of course what you gain in performance by ultra light construction you loose in the hours of time it takes to do it.
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Combatevolved
Interesting thread. I'm contemplating building a Mig 29 v1 with dual contra rotating 55mm edfs. Only problem I have is not knowing a thing about using or installing them. (More for fun than performance)
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bogusbandit56
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Interesting thread. I'm contemplating building a Mig 29 v1 with dual contra rotating 55mm edfs. Only problem I have is not knowing a thing about using or installing them. (More for fun than performance)

I don`t know much about using EDF`s but you must consider the weight of two edf`s and two ESC`s plus a battery powerful enough to keep your twin EDF`s fed on such a light air frame as the MIG29 v1.
Wot, no Depron?
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